A gear ring engine comprises a stationary outer ring and a rotor, said outer ring having teeth means at its inside, for example seven teeth, while said rotor is provided with outer teeth means, comprising for instance six teeth. The inner teeth of the outer ring can be formed by rollers. The teeth are designed such that a sealing effect occurs between the outer ring and the rotor. One half of the discplacement or gear chambers which are created between the outer ring and the rotor are connected to the high pressure side of the engine, while the other half is connected with the low pressure side. A rotating distributor valve (commutator valve) serves to control the engine. During the movement of one of the teeth of the rotor from one tooth gap of the outer ring to the next tooth gap, each tooth or gear chamber is filled and discharged once.
German patent 12 93 601 discloses a rotary piston engine having a distributor valve in which radially extending control channels and also control channels in the form of axially extending grooves are provided. Passages formed in the housing are connected with said control channels, said passages ending on one side into a bore of the housing and are connected at the other side with the gear chambers. Moreover, a ring channel is provided in the housing which is connected with the control channels having the form of grooves. The radially extending control channels lead on the other hand into the interior of a distributor valve and provide via the inner space of the rotary valve the connection to another ring channel in the housing. The ring channels located in the housing are in turn connected with bores of the housing so as to provide a connection to pressure medium. For the production of such a pump a significant amount of expenditures is required. Also, when running the engine a high level of noise is observed.
German patent 26 08 887 relates to a rotary piston engine for a liquid. In a main distributor valve of said engine control openings are provided which extend obliquely with a small angle of a approximately 3.degree. to 8.degree. with respect to the line of circumference of the appropriate control surface, wherein the control openings are sized such that control openings connected to the compression chambers are approximately exactly covered by each second sealing land (of the sealing lands which remain between the other control opening, while the control openings will be covered by the sealing lands arranged inbetween with excess (oversize). Due to these features pressure jolts in the connecting conduits are to be avoided without requiring any additional machining. In this context attention is drawn to Italian patent 425094 which discloses in FIG. 5 roof and kidney shaped passages which provide for the same effect as the oblique control openings. Page 1, lines 58 through 70 of said Italian patent notes that the selected cross section successively increases the power, so that the full cross section will not open in a shock-line manner.
It is an object of the present invention to design a rotary piston engine of the kind mentioned initially, that a simple and thus costwise favorable manufacture can be achieved without using complicated machining operations, and without having to renounce the advantages of a minimal generation of noise during operation of the engine.